The present invention relates to a potentiometer-type throttle for an electronic fuel-injection control circuit for an internal-combustion engine of the type described in my U.S. Pat. No. 4,349,000, issued Sept. 14, 1982. Reference is made to said patent for greater descriptive detail of a fuel injection engine to which the present invention is illustratively applicable.
In all internal-combustion engine fuel control systems, the objective is to control the fuel-air mixture so that, within the limits of the particular system, it will be optimum for extracting maximum power with minimum fuel consumption. The control circuit described in my said patent makes use of sensors arranged to measure or ascertain both manifold absolute pressure and manifold absolute temperature to provide a signal indicative of the air mass entering the engine during any particular incremental interval. However, differences in air density at different altitudes, and concurrent changes in exhaust back pressure due to the changes in altitude-determined ambient air pressure cause prior systems to deviate from optimum efficiency.